Propane fracs due at New Brunswick gas field

By OGJ editorsHOUSTON, May 6 -- Corridor Resources Inc., Halifax, NS, plans to use propane instead of water and methanol in a frac program at McCully gas field in New Brunswick in mid-2009.

Corridor has suspended drilling for the rest of 2009 and has redesigned the mid-2009 frac program for the P-48, L-38, C-29, and horizontal I-47 wells.

Previous high methanol concentrations reduced surface tension and prevented hydrate formation, but new evidence indicates that methanol may have reacted with the formation and caused scaling and deposition of minerals, including gypsum, in the wellbore. This appears to have impaired production performance at some wells, accentuated by the unusually low temperatures and high pressures of the McCully reservoir, Corridor said.

Fracturing with propane "is expected to minimize formation damage and to be more readily recoverable on flowback than water and methanol," the company said.

Corridor also ended pump tests at the South Branch G-36 discovery well after production fell to 5 b/d from 45 b/d of 45° gravity oil. The company is considering a refrac using propane or drilling a horizontal offset.

"The 3D seismic acquired by Corridor last fall shows extensive potential for numerous additional wells to follow up on this light oil discovery," Corridor said.

Corridor retained consulting engineers to quantify the gas resource in the Frederick Brook shale in the Sussex/Elgin subbasins and is in talks with potential partners in evaluating its holdings, especially at Elgin.